<!DOCTYPE html>
<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .div {
            width: 100px;
            height: 100px;
            border: 3px solid black;
        }
    </style>
</head>

<body>
    <div id="app">
        <div class="div" :style="{backgroundColor: 'pink', width: '400px'}">小莺</div>
    </div>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.7.16/dist/vue.js"></script>
    <script>
        const app = new Vue(
            {
                el: "#app",
                data: {
                }
            }
        )
    </script>
</body>

</html>